I finally figured out how to send and receive data to/from my RS232 Balance. It was a struggle to get the correct parameters etc. Now I have a perl script sort of working but there is a major problem. The code below is written as a TKX program. All it does is send hex strings to the scale to make it report back and also to operate the tare function. It works but only once every time I open the program. Multiple clicks on the read button (calls a sub to send characters) after the first return nothing. Tare button does nothing unless it is the first thing done after the program starts and then the scale does not respond until the program is closed. I have looked over win32::serial over and over and tried everything i could think of but nothing changes. The communication is working because the scale does report one value or does on tare operation when the program closes. sorry for all the TK stuff getting in the way. At the end is a bare bones version but it does not work for my testing because the script ends after each sent character.

#!/usr/bin/perl -w
use strict;
use Tkx;
use Win32::SerialPort;

use Cwd;
use File::Copy;
my $path = getcwd;

my $read_scale;
my $main_back_color = "#EAC9E0";
my $backcolor = "#E798FF";
my $active_color = "#D4D0C8";
my $scale;
my $maintitle = "Read Sartorius";
my $version = " version 1.000";

Tkx::catch("console hide");
my $mw = Tkx::widget->new(".");
$mw->g_wm_resizable(0,0);
$mw-> g_wm_title($maintitle);
$mw->g_grid_columnconfigure(0, -weight => 1);
$mw->g_grid_rowconfigure(0, -weight => 1);

Tkx::font_create("headtext_font",-size => 14);
Tkx::font_create("scale_font",-size => 10);
Tkx::font_create("bold_label_font", -size => 12, -weight=> 'bold');
Tkx::font_create("small_button_font", -size => 6,-weight=> 'normal');

my $menu = $mw->new_menu;
$mw->configure(-menu => $menu);
my $std_fncts = $menu->new_menu;
my $test = $menu->new_menu;
$menu->add_cascade(-menu => $test, -label => "Help");
$test->add_command(-label => "no Help yet", -command =>
    sub {fill_help("F");do_help(25,100);});

$menu->add_command(-label => "Exit", -command => sub{\&clean_exit()});

my $frame0 = $mw-> new_frame(-relief=>'raised',-borderwidth=>2,-bd=>1,
+-background=> "$backcolor");
$frame0->g_grid(-column =>0, -row => 0,-sticky => "ns");

my $buttons = $frame0-> new_frame(-bd=>2,-relief=>'raised',-relief=>'r
+aised'); #,-background =>$check_button_color);
$buttons->g_grid(-column =>0,-rowspan => 2, -row => 4,-sticky => "nsew
+");

my $readbut = $buttons->new_button (-text => "Read", , -width=> 11,-co
+mmand => sub {read_scale();}, -background => "green", -activebackgrou
+nd => "red", -pady => 5, -padx => 6);
$readbut -> g_grid(-column =>0, -row => 0, -sticky => "E");

my $tarebut = $buttons->new_button (-text => "Tare", -width=> 10, -com
+mand => sub {tare_scale();}, -background => "red", -pady => 5, -padx 
+=> 3);
$tarebut -> g_grid(-column =>1, -row => 0, -sticky => "E");

my $lblscale = $buttons->new_label (-text => "Scale");
$lblscale -> g_grid(-column => 0, -row => 1, -sticky => "w");

my $eread_scale = $buttons->new_entry (-width => 15, -textvariable => 
+\$read_scale);
$eread_scale -> g_grid(-column => 1, -row => 1, -sticky => "w");

my $PORT = "COM1"; # port to watch
my $ob = Win32::SerialPort->new ($PORT) || die "Can't Open $PORT: $!";
$ob->baudrate(1200) || die "failed setting baudrate";
$ob->parity("odd") || die "failed setting parity";
$ob->databits(7) || die "failed setting databits";
$ob->handshake("rts") || die "failed setting handshake";
$ob->stopbits(1) || die "failed setting stop bits";;
$ob->write_settings || die "no settings";

sub read_scale{
    $ob->transmit_char(0x1b);
    $ob->transmit_char(0x50);
    $ob->transmit_char(0x0d);
    $ob->transmit_char(0x0a);
    sleep .2;
    my $result = $ob->input;
    $read_scale = ($result);
    print "result = $result\n";
    my $got_it = $ob->lookfor;
}
sub tare_scale{
    $ob->transmit_char(0x1b);
    $ob->transmit_char(0x54);
    $ob->transmit_char(0x0d);
    $ob->transmit_char(0x0a);
}

sub clean_exit{    
     undef $ob;
     exit;
}
Tkx::MainLoop();
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$PORT = "COM1"; # port to watch
$ob = Win32::SerialPort->new ($PORT) || die "Can't Open $PORT: $!";
$ob->baudrate(1200) || die "failed setting baudrate";
$ob->parity("odd") || die "failed setting parity";
$ob->databits(7) || die "failed setting databits";
$ob->handshake("rts") || die "failed setting handshake";
$ob->stopbits(1) || die "failed setting stop bits";;
$ob->write_settings || die "no settings";

# Send a hex string to the port

my $sendP = pack('C*', 0x1b, 0x50); # the print command
my $sendT = pack('C*', 0x1b, 0x54); # the tare command
my $pass=$ob->write($sendP);
sleep 1;
my $result = $ob->input;
print "result = $result\n";

undef $ob;
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